This invention relates to an electromagnet for use with an electrically controlled brake. More specifically, the invention relates to an electromagnet of the same general type as disclosed in Myers et al U.S. Pat. No. 4,172,242. That magnet includes a plate stamped from magnetic sheet metal and further includes at least one pole which is defined by a stud adapted to be formed from inexpensive bar stock and adapted to be easily assembled with the stamped plate.
An electrical coil surrounds the stud and, when the coil is energized, the poles of the magnet are attracted toward an armature and frictionally retard the armature. The primary friction face of the magnet is formed by a piece of friction material which fills the spaces between the poles. In the magnet disclosed in the Myers et al patent, the friction material is in the form of a rather thick block whose outer active face is substantially flush with the outer end of the stud.
While the magnet of the Myers et al patent lends itself to being manufactured in a comparatively economical manner, the thick block of friction material is relatively expensive. Also, it is necessary to replace the entire electromagnet once the poles and the active face of the friction block have experienced excessive wear.